In unducted fan propulsor engines for aircraft, the pitch of the propulsor blades is adjustable to prevent propulsor overspeed. With such systems, an overspeed governor is required to prevent propulsor overspeed in the event of normal electronic control failure. Due to the high torque inertia ratio of the propulsor, rapid accelerations of the propulsor are possible. Normal flyweight governors can not respond fast enough to prevent a dangerous overspeed condition. Therefore, governing is required to begin before the normal point when rapid accelerations are present.